Machine expressivity is often thought of as involving precision, speed, rhythmic complexity, non-idiomatic (for human performers) pitch patterns and replication. Human expressivity is often thought of involving groove, phrasing, affect, contour, variation, articulation, entrainment and communication. While these attributes help shape our conceptions of what is human versus what is mechanical, they are not confined to one category or the other: humans can be precise and robots can groove. Expressive identity is more analog than digital. This does not preclude expressive spaces that are unique to humans and machines, rather, it suggests the areas between them are ambiguous and that the attributes that define them do not do so in a one-to-one fashion (instead, attribute-space relationships are a function of combination and context). The music explores these areas of ambiguity and clarity. Genre is treated in a similar way such that stylistic exemplars are presented authentically and in transformation. The intersections in expressive identity and style illuminate what is exclusive and what is shared.

Performed by the Juventas New Music Ensemble and the musical robots PAM and CADI, which were designed and built by EMMI and the Music, Perception and Robotics Lab at WPI.